/**
 * Copyright (C) 2009 - present by OpenGamma Inc. and the OpenGamma group of companies
 * 
 * Please see distribution for license.
 */
package com.opengamma.financial.convention.daycount;

import org.threeten.bp.LocalDate;
import org.threeten.bp.ZonedDateTime;

/**
 * The '30U/360' day count.
 */
public class ThirtyUThreeSixty extends ThirtyThreeSixtyTypeDayCount {

  /** Serialization version. */
  private static final long serialVersionUID = 1L;

  @Override
  public double getDayCountFraction(final LocalDate firstDate, final LocalDate secondDate) {
    return getDayCountFraction(firstDate, secondDate, false);
  }

  public double getDayCountFraction(final ZonedDateTime firstDate, final ZonedDateTime secondDate, final boolean isEOMConvention) {
    return getDayCountFraction(firstDate.toLocalDate(), secondDate.toLocalDate(), isEOMConvention);
  }

  public double getDayCountFraction(final LocalDate firstDate, final LocalDate secondDate, final boolean isEOMConvention) {
    testDates(firstDate, secondDate);
    double d1 = firstDate.getDayOfMonth();
    double d2 = secondDate.getDayOfMonth();
    final double m1 = firstDate.getMonthValue();
    final double m2 = secondDate.getMonthValue();
    final double y1 = firstDate.getYear();
    final double y2 = secondDate.getYear();
    if (isEOMConvention && m1 == 2 && isLastDayOfFebruary(firstDate) && isLastDayOfFebruary(secondDate)) {
      d2 = 30;
      d1 = 30;
    } else {
      if (d1 > 29 && d2 == 31) {
        d2 = 30;
      }
      if (d1 == 31) {
        d1 = 30;
      }
    }
    return getYears(d1, d2, m1, m2, y1, y2);
  }

  public double getAccruedInterest(final ZonedDateTime previousCouponDate, final ZonedDateTime date, final double coupon, final boolean isEOMConvention) {
    return coupon * getDayCountFraction(previousCouponDate, date, isEOMConvention);
  }

  public double getAccruedInterest(final LocalDate previousCouponDate, final LocalDate date, final double coupon, final boolean isEOMConvention) {
    return coupon * getDayCountFraction(previousCouponDate, date, isEOMConvention);
  }

  @Override
  public String getName() {
    return "30U/360";
  }

  /**
   * Checks if the date, which must be in February, is the last day.
   * 
   * @param date  the date to check, not null
   * @return whether it is the last day
   */
  private static boolean isLastDayOfFebruary(final LocalDate date) {
    return date.getDayOfMonth() == date.lengthOfMonth();
  }

}